Yes it's kiln dried, I figured everyone would assume that? The thicker stuff is for chickens/horses/etc. The finer stuff is for rabbits, rats, etc.
I understand most people wouldn't use pine for rats, but I've been keeping rats on it for 3 years. I've got one female who will be three next month, a male that is probably already three, if not he's really close, I'm not sure what month he was born I got him as a small adult. I've never had a rat die-due to old age-under 2.5 years old, so in my experience, I don't think pine is any more dangerous than aspen/pellets/corn cob/etc. I did bring home a pet store plague that wiped out a bunch of my rats about two years ago, other wise I would have had a lot more rats make it to old age.